FIELD OF THE INVENTION
This invention relates to an improved rotating platform apparatus, which is useful for recreation and exercise. The prior art discloses a variety of riding, rocking and turning toys, wobble plates, and swivel platforms, which are expensive to manufacture, have limited utility, or provide safety hazards. Many of these prior art devices have not reached the market place for the reasons noted above.
U.S. Pat. No. 3,088,733 issuing to R. Ayers on May 7, 1963 discloses a riding toy having an inclined platform supported on an obtusely angulated rod secured to the base. The rotation of the inclined platform is limited by the friction of the angulated rod as it rotates within a sleeve without the aid of bearings. The inclined platform is smaller than the base, and both the inclined platform and the base are supported by radially extending angle iron secured to the sleeve.
U.S. Pat. No. 4,290,601 issuing to R. Mittelstadt on Sep. 22, 1981 discloses a wobble plate having a peripheral roller support comprising rollers which contact the underside of treadle board 10 in proximity to the outer periphery of the treadle board. The user may accidentally grab the outer periphery of the treadle board during rotation while attempting to maintain balance, which poses a safety hazard by getting one's fingers between the rollers and the underside of the wobble board.
U.S. Pat. No. 4,193,592 issuing to R. Bishow on Mar. 18, 1908 discloses a rocking, turning toy for use in a sitting, standing or kneeling position. The base has an enlarged protuberance with a flat bottom. A caster assembly is located between the top surface of the lower member and the lower surface of the top member. A shaft extends from the lower surface. The device rotates about the shaft, and rocks upon the enlarged protuberance.
The following patents are representative of other rotating platforms found in this art. They are U.S. Pat. Nos. 5,368,536; 5,279,533; 4,953,858; 4,687,198; 4,605,224; 3,593,994 and 1,565,484.